This invention relates generally to protective tape, and more particularly to a laminated shielding tape capable of preventing cross talk interference and other related electromagnetic interference in wiring systems.
The present invention represents an improvement in tape used as a shield against electromagnetic interference (EMI) and radio frequency interference (RFI) in wiring systems for aircraft and the like. Such tape is used in wiring systems having a plurality of wires or cables which transmit information. One problem associated with typical wiring systems is that cross talk and electromagnetic interference occurs between adjacent wires or groups of wires operating at similar frequencies. In order to prevent cross talk and electromagnetic interference, tape is disposed around or between the wires for shielding and supporting them.
One tape composition known in the art comprises a layer of one ounce copper foil sandwiched between two layers of 0.00092 inch polyethylene terephthalate ("PET"). One ounce copper foil is defined in the art as a copper foil having a weight of one ounce per square foot of material. In use, the prior art tape is usually stripped at its ends i.e. the PET layers removed to expose the copper layer for soldering to a ground wire, or termination. When the copper layer is to be soldered, the stripped copper end is dipped in tin to provide an appropriate soldering surface. The tin coated copper layer is then soldered to a grounding wire. One problem discovered with this composition is that the tape has a tendency to crack and fail at the location of the juncture of the copper and partially stripped PET layers. More specifically, the copper tears, ruptures or cracks at the exposure site. There is presently a need for a shielding tape capable of protecting wires subjected to cross talk and electromagnetic interference while maintaining its structural integrity.
In general, the present invention is directed to a shielding tape for use with communication wiring susceptible to cross talk and electromagnetic interference. The shielding tape comprises a protective component having a metallic layer for shielding and protecting the communication wiring from cross talk and electromagnetic interference, and a structural component having a layer of fiberglass disposed between two layers of polyethylene terephthalate ("PET").
Accordingly, among the several objects of the present invention are the provision of a shielding tape which is capable of preventing cross talk and electromagnetic interference between wires of a wiring system; the provision of such a shielding tape which is durable in construction and is resistent to failure after a period of use; the provision of such a shielding tape which is reliable and requires less maintenance than prior art tape; the provision of such a shielding tape which is capable of being utilized in a variety of different fashions; and the provision of such a shielding tape which is easy and cost-efficient to use.